Since there is a project to deploy an x86 VyOS as the router, After I install the system and I find out that I can use the console to connect to the system just like other Cisco(H3C) routers rather than using the screen.

However, The Cisco router are using RS232-RJ45 port, and I just spot that the H61 MotherBoard ais using jcom jumper to the DB9 male port. And my USB-RS232 converter is also with the DB9 male port, so I’d like to make a jcom to DB9 female plan.

I just find out some jcom and DB9 information here,

JCOM jumper on the motherboard

② RXD

④ DTR

⑥ DSR

⑧ CTS

EMPTY

① DCD

③ TXD

⑤ GND

⑦ RTS

⑨ RI

JCOM line

First is red -> -> ->

①DCD ②RXD ③TXD ④DTR ⑤GND ⑥DSR ⑦RTS ⑧CTS ⑨RI

As usual, when communicating via the RS232, a PC is as the DTE, but as I am using the PC being the router, it is becoming the DCE, so it’s essential to switch the RXD and TXD.